This invention relates to photographic cameras and more particularly, it concerns a flash lamp diffuser retracting and erecting mechanism for use primarily, though not exclusively, in collapsible bellows type cameras.
Collapsible cameras for large format films conventionally include a back housing for supporting film in a position to be exposed through a lens aperture in a shutter housing connected to the back housing by a foldable bellows. The shutter housing is supported by an erecting linkage in a manner facilitating its movement between a collapsed condition against the back housing and an erect or operative condition in which the lens is properly spaced from and aligned with the film in the back housing. The bellows, being foldable, provides light-tight enclosure between the respective housings at all times. Also a protective cover is usually associated with the erecting linkage in a manner to pivot between a closed position over the shutter housing and bellows in the collapsed condition of the camera and an open position upon erecting the camera for operation.
The shutter housing of such cameras typically contains apparatus for determining the parameters for film exposure, such as a shutter and lens aperture stopping means as well as electrical equipment usually including a light meter and/or an automatic exposure control system. Because of the supply of electrical current available as well as the proximity of shutter synchronization switching, it is common practice to mount a flash illumination receptacle also on the shutter housing. The connection of such receptacles to a remote flash lamp mounted on the back housing or elsewhere on the camera and using an electric cord equipped with an appropriate plug is well-known in the art. Collapsible cameras have also incorporated receptacles for rotatable, multi-flash units known as "flash cubes."
Commercially available flash cubes are accepted as desirable because of the facility they provide for making multiple flash exposures without requiring replacement of the unit for each such exposure. In large format cameras, however, flash cubes are most advantageously used with a diffuser by which the illumination emanating from each flash unit will be spread over a sufficiently large area to assure proper exposure of the complete area of the film to be exposed. Because the diffuser is physically embodied in plate-like shield positioned in front of the flash cube, it also serves a measure of protection against accidental flash unit explosion or shattering.
In collapsible cameras of the type referred to, the proximity of the shutter and electric circuitry in the shutter housing, gives rise to economic advantages in mounting a flash cube on the shutter housing. Also the provision of a flash cube receptacle on the shutter housing serves to protect the receptacle as a result of its being enclosed by the cover of the camera when the latter is in a collapsed condition. In view of the space limitations about the shutter housing in a collapsed bellows camera, however, it is difficult to accommodate a flash diffuser. Although the diffuser might be hinged or otherwise folded against a face of the shutter housing, use of the diffuser in practice will be insured only if it is properly positioned automatically when the camera is erected and thus conditioned to receive a flash cube.